Fusarium head blight of wheat: evaluation of the efficacies of fungicides towards Fusarium graminearum 3-ADON and 15-ADON isolates in spring wheat and assess the genetic differences between 3-ADON isolates from Canada and China

Abstract

Fusarium head blight (FHB), caused mainly by Fusarium graminearum, is one of the most destructive global diseases of small cereal grains worldwide. The most devastating effect of this disease is the deposition of mycotoxins in the grain. Deoxynivalenol (DON) and its analogs 3-ADON, 15-ADON and NIV are the major mycotoxins produced by the fungus. The chemotype, 15-ADON is more prevalent in North America, but recently a chemotypic shift has been observed. The rapid emergence of the 3-ADON chemotype over the traditional 15-ADON chemotype is a major concern in North America. The studies in this thesis were focused on understanding the behaviour of the 3-ADON and 15-ADON chemotypes and the possible reasons for the rapid chemotypic shift.